function checkForValidUrl(tabId, changeInfo, tab) {
	if (tab.url.indexOf('grooveshark.com') > -1) {
		chrome.pageAction.show(tabId);
	}
};

chrome.tabs.onUpdated.addListener(checkForValidUrl);

chrome.pageAction.onClicked.addListener(function(tab) {
  chrome.tabs.executeScript(tab.di,{file: "content_script.js"});
});

